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Home >> Chevrolet >> 2002 >> Malibu Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Self-Diagnostics - 3.1L Engine >> Inspection/Maintenance Procedures >> Inspection/Maintenance Heated Oxygen Sensor (Ho2S) Heater System Set Procedure >> Diagnostic Procedures
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Diagnostic Procedures

  1. Did you perform the Inspection/Maintenance (I/M) System Check? If yes, go to next step. If no, go to INSPECTION/MAINTENANCE SYSTEM CHECK .
    NOTE: Whenever ignition is turned ON, ignition positive voltage is supplied to HO2S heaters. After verifying the enable criteria, turn off the ignition for about 5 minutes to allow the sensors to cool before continuing with the test.
    • Preprogram the scan tool with the vehicle information before the ignition is turned ON.
    • Ensure vehicle is within the Conditions For Running Test.
    • Set vehicle parking brake.
    • Place transmission in Park (A/T) or Neutral (M/T).
    • Turn off all of accessories (e.g., A/C, blower fan, etc.).
    • Start engine and allow engine to idle.
    • Allow engine to idle for the specified time or until the I/M System Status indicator updates to YES.

    Did the HO2S Heater system Status update to YES? If yes, go to step  5. If no, go to next step.

  3. Using scan tool, observe DTC information. Does the scan tool indicate any failed DTCs? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, go next step.
    NOTE: Refer to INSPECTION/MAINTENANCE SYSTEM DTCS  to determine which DTCs are required to run in order to complete this test.
  4. Using scan tool, observe the NOT RAN SINCE CODE CLEARED display. Determine which of the DTCs required for a YES status has not run. Operate vehicle within the Conditions For Running Test. See CONDITIONS FOR RUNNING TEST . Monitor status of DTCs that are necessary to complete the test in the NOT RAN SINCE CODE CLEARED display of scan tool. Repeat procedure until scan tool indicates that all the necessary DTC diagnostic tests have run. Using scan tool, observe I/M system Status display. Did the HO2S Heater system Status update to YES? If yes, go to next step. If no, go to DIAGNOSTIC AIDS .
  5. Using scan tool, observe emission related DTC portion of I/M system Status display. Does the scan tool indicate any emission related DTCs set? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.
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